The invention relates in general to optical connections to microchips, and more particularly to optical connections to microchips having an effective environmental seal.
Micro-optical electromechanical systems (MOEMS) is a relatively new technology. Traditional optical packages are hermetic at the carrier level. These packages are very expensive from a materials and fabrication standpoint. In addition, the critical optical components are not protected until the final packaging step, which typically lowers yield. Greater losses are incurred when yield losses are experienced in this final packaging step. Also, because a greater variety of materials exist inside the larger carrier level package, reliability concerns are amplified due to out gassing and corrosion, often limiting material selection.
U.S. Patent Application Publication 20020090761 discloses a hermetic sealing method for an electronic circuit module, however, it does not disclose a method of sealing a fiber optic into the circuit module.
U.S. Pat. No. 6,300,151 discloses a method of aligning an optical fiber to an optical module. However, the fiber interconnect and hermetic sealing is not discussed.
U.S. Pat. No. 6,019,523 discloses a method of aligning an optical fiber. A noise reducing seal is made from the external environment. The seal is not hermetic. It is possible that moisture may enter through the entire package.
U.S. Pat. No. 5,852,696 relates to a coupling structure of an optical fiber and an optical semiconductor element. A V groove is formed using known masking and anisotropic etching techniques. An optical fiber is bonded into the V groove using an index matching UV curable adhesive or other suitable known adhesive. A chip and optical fiber hermetic seal is not disclosed.
U.S. Pat. No. 5,717,803 discloses optical fibers arranged in a V groove formed at the surface of a silicon substrate and a cover provided thereon. This is an optical coupling device without an environmental seal.
It is an object of the invention to hermetically seal a top chip and an optical fiber interconnect to a micromachined device, thereby eliminating the need for a hermetic carrier level package.
The invention will be better understood, and further objects, features, and advantages thereof will become apparent from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings.